Indian Oil Corporation Ltd. / cheating in petrol filling

This is in regard of my experience with a Sukhwani petrol pump at waked chowk pune its Indian Oil Petrol Pump.
I filled petrol of 530 rs ( wanted to fill 500 rs petrol) the petrol attendant engrossed me in talks to fill 530rs petrol and while I was having conversation with him he made sure I dint pay attention towards zero meter and he started filling from 250rs (filled previously for bike) and when I confronted the petrol pump attendant for the same, it lead to 3 4 people arguing n fighting with me for the same.Kindly look into this matter as we as consumers feel cheated for the hard earned money.
Please consider my complain seriously